<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        /* .box{
            width: 100px;
            height: 100px;
            background-color: blue;
            margin-bottom: 10px;
        }
        #test{
            background-color: red;
            position: relative;
            left: 20px;
            top: -20px;
        } */
        .box2{
            border: solid 1px red;
            width: 300px;
            height: 150px;

        }
        .box3{
            background-color: aqua;
            width: 100px;
            height: 100px;
            position: absolute;
            top: 5px;
            left: 5px;
        }
    </style>
</head>
<body>
    <div class="box"></div>
    <div class="box" id="test"></div>

    <div class="box2">
        <div class="box3"></div>
    </div>
</body>
</html>